Federal Reserve Chairman Ben Bernanke (left) talks with Susan Collins, dean of the public policy school at the University of Michigan, in Jackson Hole, Wyo. AP

Chairman Ben Bernanke sent a clear message Friday that the Federal Reserve will do more to help the still-struggling U.S. economy.

Bernanke described the U.S. economy’s health as “far from satisfactory” and noted that the unemployment rate, now 8.3 percent, hasn’t declined since January.

He stopped short of committing the Fed to any specific move. But in his speech to an annual Fed conference in Jackson Hole, Wyo., Bernanke said that even with interest rates already at super-lows, the Fed can do more.

Stocks and Treasurys climbed Friday and the dollar weakened to a more than three-month low as investors speculated steps to boost the economy may come as soon as next month.

“The costs of nontraditional policies, when considered carefully, appear manageable, implying that we should not rule out the further use of such policies if economic conditions warrant,” he said.

The Dow Jones industrial average added 90.13 points to 13,090.84, and finished the month of August up by 0.8 percent. The Standard & Poor’s 500 index increased 7.10 points to close at 1,406.58, rising more than 2 percent for August and capping its third straight monthly gain. The Nasdaq rose 18.25 points to close at 3,066.96, up more than 4 percent for August.

Policy makers at their July 31-Aug. 1 meeting were moving toward additional action, according to minutes released last week. Many members of the panel said more stimulus will be needed “fairly soon” unless the recovery shows signs of a “substantial and sustainable strengthening.”

Speaking Friday to central bankers and economists two weeks before the next meeting of the Federal Open Market Committee, Bernanke emphasized that a new round of bond purchases is an option. Some economists predict the Fed will possibly unveil a third round of bond purchases meant to lower long-term interest rates and encourage more borrowing and spending. That policy is called “quantitative easing,” or QE.

Others expect something less dramatic: a plan to keep short-term rates near zero into 2015 unless the economy improves, perhaps followed by bond purchases later.

“The door is wide open to the Fed contemplating additional action,” said Josh Feinman, a former Fed senior economist who helps oversee $219 billion at Deutsche Bank’s asset management unit in New York. “It reaffirms other messages sent by the Fed that additional action is still very much on the table. By the end of the year we’ll probably get both rate guidance extension and more asset purchases.”

In two rounds of QE, the Fed bought more than $2 trillion of Treasury bonds and mortgage-backed securities. Many investors have been hoping for a third round — a QE3.

Bernanke, 58, also argued that the Fed’s moves so far to keep interest rates at record lows and encourage borrowing and spending have helped bolster the economy.

Even if the Fed does act further, many analysts doubt it would make much difference. Interest rates, both short- and long-term, are near historic lows. Borrowing — for those who have the credit — has never been cheaper. Yet the economy remains in a rut.